1. Technical Field
The present invention relates to a method of preparing an optical material by polymerizing a resin composition including a thiol group-containing compound and an isocyanate group-containing compound, and more particularly, to a method of preparing a high-quality urethane-based optical material using a widely available polyisocyanate compound, a resin composition for the same, and an optical material prepared using the resin composition.
2. Description of Related Art
Plastic optical materials are lightweight and possess superior impact resistance and are easily dyed, as compared to optical materials formed of inorganic materials. In recent years, a variety of resins and plastic materials have been used in optical materials, and property expectations therefor have also been raised.
A polythiourethane optical resin prepared using a polythiol compound and an isocyanate compound has been widely available for optical lenses due to excellent optical properties such as transparency, Abbe number, transmittance, and tensile strength. However, polymerization imbalance and white tape residue generation, which generally occur during preparation of an optical material by curing a resin composition including a polythiol compound and a widely available isocyanate compound, are responsible for deterioration of optical properties of the optical resin. Particularly, white tape residues and foams adversely affect performance of the optical material, bringing about defects and deterioration of lenses.